School of Pharmacy , Qilu Medical University , Zibo Economic Zone , Zibo City 255300 , Shandong , People's Republic of China.
Department of Chemistry , The University of Manchester , Manchester M13 9PL , United Kingdom.
J Phys Chem A. 2019 Dec 12;123(49):10500-10513. doi: 10.1021/acs.jpca.9b07959. Epub 2019 Dec 2.
We analyze the physical content of structures present in the product differential cross sections (DCSs) of the benchmark F + H(, , ) → FH(, , ) + H reaction, where , , and are the vibrational, rotational, and helicity quantum numbers, respectively, for the initial and final states. We analyze three state-to-state transitions: 000 → 300, 000 → 310, and 000 → 320. Accurate quantum matrix elements are employed at a translational energy of 0.04088 eV for the Fu-Xu-Zhang potential energy surface. Our analysis of the DCSs uses a new technique called the QP decomposition; it makes an exact decomposition of the scattering () matrix into a Q part and a P part. The P part consists of a partial wave (PW) sum of Regge poles (involving both positions and residues) together with a rapidly oscillating quadratic phase. The Q part of the decomposition is then constructed exactly by subtracting the rapidly oscillating phase and the PW Regge pole sum from the input PW matrix. In practice, it is convenient to make a small modification, which we call the QmodPmod decomposition. All our calculations use only integer values of the total angular momentum quantum number, namely, = 0, 1, 2,... We find that the QmodPmod decomposition is successful and physically meaningful, in that the properties of Qmod matrix are simpler than those of the input matrix. We then carry out a QmodPmod analysis of the DCSs, which provides novel insights into interference structures present in the angular scattering. In particular, we find for all three reactions that Regge resonances contribute across the whole angular range of the DCSs, being particularly pronounced at small angles. The techniques of nearside-farside decomposition and local angular momentum analysis for resummed Legendre PW series are also employed to provide additional insights into the angular scattering.
我们分析了基准 F + H(,, ) → FH(,, ) + H 反应产物微分截面 (DCS) 中存在的物理结构，其中,, 和 分别是初始和最终态的振动、转动和螺旋量子数。我们分析了三个态到态的跃迁：000 → 300、000 → 310 和 000 → 320。在 Fu-Xu-Zhang 位能面上，我们采用准确的量子 矩阵元，在 0.04088 eV 的平移能下进行计算。我们对 DCS 的分析采用了一种称为 QP 分解的新技术；它对散射 () 矩阵进行了精确的 Q 部分和 P 部分分解。P 部分由 Regge 极点（包括位置和残数）的部分波（PW）和快速振荡的二次相位组成。分解的 Q 部分通过从输入 PW 矩阵中减去快速振荡相位和 PW Regge 极点和来精确构建。在实践中，方便地进行一个小的修改，我们称之为 QmodPmod 分解。我们的所有计算都只使用总角动量量子数的整数值，即 = 0, 1, 2,... 我们发现 QmodPmod 分解是成功的，具有物理意义，即 Qmod 矩阵的性质比输入 矩阵的性质更简单。然后，我们对 DCS 进行了 QmodPmod 分析，这为角散射中存在的干涉结构提供了新的见解。特别是，我们发现对于所有三个反应，Regge 共振在 DCS 的整个角域中都有贡献，在小角度处特别明显。还采用了近侧-远侧分解和重排 Legendre PW 级数的局部角动量分析技术，以提供对角散射的更多见解。
